Patent GB-687333-A (GB)
Title: Improvements in or relating to receiving relays remote control
IPC: H02J13/00
Filed: 1951-10-08
Abstract: 687,333. Actuation of switches. COMPAGNIE POUR LA FABRICATION DES COMPETEURS ET MATERIEL D'USINES A GAZ. Oct. 8, 1951 [Oct. 9, 1950, March 30, 1951 No. 23400/51. Class 38 (v) [Also in Group XXXVIII] In remote control systems wherein selected operations are performed by superposing audio frequency, current impulses on distribution networks, the particular operation being determined by the time interval between a starting impulse and an executive impulse, the starting impulse sets in operation a motor 15 which drives two shafts 18, 21. The shaft 18 rotates a considerable number of times before the motor stops and carries a cam 37. The shaft 21 moves more slowly and makes one revolution only before the motor stops and carries, pairs of discs such as 47, 48 with adjustable tappets 51, 52 adapted to engage levers 54, 55 and so move contacts 64, 64<SP>I</SP> in a controlled circuit first into and then out of engagement but engagement of the levers 54, 55 is only possible if the levers 54, 55 are first tilted closer to the tappets by a bar 43 and this can only occur if the executive impulses are received at appropriate times. These times are such that the interval between the starting impulse and an executive impulse is an uneven multiple of an elementary time period. If the interval is an even multiple no operation occurs. The elementary time period corresponds to half a revolution of the shaft 18 or cam 37 and an appropriate time for an impulse is therefore one when the narrow portion of the cam 37 is opposite a cylinder 33. When an impulse occurs an electromagnet 8<SP>I</SP> is energized, its armature 1D pivots about an axis 10<SP>I</SP>, and a shaft 53 carrying the cylinder 33 is moved to the right. If the timing of the impulse is inappropriate the cylinder 33 engages the side of the cam 37. If it is appropriate it moves beneath the edge of the cam and is held there by a spring-biased forked lever 39 moving across its end. The subsequent rotation of the cam 37 moves the cylinder 33 so as to rotate a shaft 36 and move the bar 43 so that the levers 54, 55 are engageable by the tappets 51, 52 as previously described and the contacts 64, 64<SP>I</SP> operated. The rotation of the cam 37 also causes the lever 39 to be engaged by a pin 38 thereby releasing the cylinder 33 so thaf this is returned to its original position by the armature 10 of the now de-energized magnet 8<SP>I</SP>. The energization of the magnet 8<SP>I</SP> by an impulse superposed on the line 1, 1<SP>I</SP> may be effected as in Fig. 1 by means of a tuned relay having a tuned circuit 3, 4, a permanent magnet 7 and a tuned reed 2 carrying a contact 6. An impulse of suitable frequency will set the reed 2 in vibration and siibstantially open, at the contact 6 a short circuit of the magnet 8<SP>I</SP> so that the magnet 8<SP>I</SP> is energized. Alternatively, Fig. 3, the vibration of the reed 2 rotates a toothed or rubber wheel 102 causing centrifugal weights 107 and 108 to fly outwards and move a plunger 116 to operate contacts 117, 118 in the circuit of the magnet 8<SP>I</SP>. When the starting impulse thus energizes the magnet 8' the armature 10 in addition to moving the cylinder 33 against the face of the cam 37 releases a spring blade 13 so that contacts 13, 14 are closed and the motor 15 started. Cams 22, 23 driven respectively by the shafts 18, 21 then operate a lever 26 which by means of a pin 29 moves both contacts 14, 13 to the right and holds them there in engagement till at the end of the single revolution of the shaft 21 the notch in the cam 23 releases the spring 14 to open the motor circuit, the finger 12 on the armature 10 having in the meantime latched the spring 13 again.